Pneumatic player-action.



E. G. HISCOUK. PNEUMATIC PLAYER ACTION. APPLIOATION FILED SEPT.17. 1910.

Patented Mar. 10, 1914.

UNITED STATES PATENT OFFICE.

EMORY C. HISCOCK, OF CHICAGO, ILLINOIS, ASSIGNOR TO W. W. KIMBALLCOMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

PNEUMATIC PLAYER-ACTION.

Original application filed March 2, 1910, Serial No. 5462,8023.

Specification of Letters Patent.

Serial No. 582,451.

To all whom it may concern:

Be it known that I, EMORY C. Hrsooox, a citizen of the United States,residing in Chicago, in the county of Cook and State of Illinois, haveinvented certain new and useful Improvements in Pneumatic Player-Actions, of which the following is a specification.

This invention relates to pneumatic actions for mechanical pianoplayers, and has reference more particularly to improvements in thatclass or type of such pneumatic actions as employ a main exhaust chamberor chest which is in free communication with one side of a diaphragmthat actuates a valve controlling the alternate communica tion of theatmosphere and the exhaust with the interior of the action bellows, andis also in valve-controlled communication with the opposite side of thesaid diaphragm and with the tracker-range. in mechanisms of thischaracter there'is commonly employed a vent regulating or bleed valvethat regulates the effect of the exiaust in the main exhaust chamber orchest upon the tracker-range and one side of the said diaphragm. Thesevent regulating valves, of which there is one for each pneumatic, arecommonly of the needle valve variety having a screw-threaded mountingwhereby they are capable of fine adjustment to secure exactly therequired venting effect upon the air in the tracker and diaphragm ducts.The proper adjustment of these numerous valves is a matter ofconsiderable nicety, requiring a high degree of skill and involvingconsiderable labor and experi ment; and as these valves have hithertobeen commonly located in position more or less difficult of access, theproper regulation of the act-ion in this respect has proved a source ofconsiderable diiliculty and expense to manufacturers of theseinstruments.

The main object of the present invention has been to provide such astructure and organization of the parts, including the vent regulatingvalves, as would render the latter most easy of access for purposes ofadjustment and most eflicient in operation; and with this object inview, the invention com prises as its main feature the location of suchvent regulating valve in the unobstructed front Wall of the main exhaustchamber having a duct communicating with As is well known,

exhaust chest, underlying diaphragm cham ber, and the tracker range of awell-known form of player piano.

Referring to the drawing, 10 designates the main exhaust chamber orchest, above which pipes 11 lead to the usual tracker range 12 of theinstrument. Each pipe 11 connects with a vertical duct 13 formed throughthe back wall of the exhaust chest 10, said. duct 18 connnunicating witha horizontal duct i lin the forwardly extending bottom wall of theexhaust chamber 10, and the duct 14 communicating with a vertical duct15, the lower end of which communicates by a short inwardly extendingduct 16 with the lower side of a diaphragm 17 mounted in. the bottom ofa diaphragm chamber 18, which latter is in communication with andsubject to the same degree of vacuum as that existing in the exhaustchamber 10. Mounted on the diaphragm 17 is a T-shaped valve 19 whichextends upwardly into a valve chamber 20 above the diaphragm chamber 18and cooperates alternately with lower and upper valve seats 21 and 22 atthe lower and upper ends of said valve chamber 20, respectively. he stemof the valve 19 is hollow and is guided on a vertical pin 23 dependingfrom the upper annular valve seat 22. From the valve chamber 20 a duct24 leads directly into the action bellows 25; while, when the valve 19is withdrawn from its upper seat 22, the upper end of the valve chamber20 is in free communication with the atmosphere through said hollowvalve seat and a horizontal duct 26 lying between the ducts 14 and 24.

The front wall of the exhaust chest 10 has a series of vertical ducts 27that communicate at their lower ends with the ducts 14L. Mounted in thefront wall of the exhaust chest 10 and intersecting each of the verticalducts 27 is a hollow valve-holder or casing 28 of a generallycylindrical form having a head 29, a threaded bore, and a substantiallycentral circun'iferential groove 30 lying in the vertical plane of theduct 27, with one or more radial holes 31 forming a communicationbetween the groove 30 and the interior of the valve-holder. This latteris also formed with a contracted portion forming an internal valve seat32 at its inner end adapted to be controlled as a vent opening betweenthe exhaust chest 10 and the duct 27 by a needle valve 33 that is formedwith a screw-threaded stem or shank 34: having threaded engagement withthe bore of the holder or *alve-casing 28. This valve holder ispreferably made of hard rubber or what is known as hard rubbercomposition, since I have determined by experiments that this materialis free from contraction and expansion at ordinary room temperatures toany such extent as to displace the valve from correct adjustment; and italso grips the stem or shank of the valve under a high degree offriction, and thus prevents accidental turning of the valve therein. Thenovel details of the valve, per so, however, form no part of the presentinvention, but are made the subject matter of an application filed by meon the 2nd day of March 1910, Serial No. 546,809, of which the presentapplication forms a division.

In player pianos, the mechanism of the pneumatic action herein shown isusually nounted in such a way that the removal of the upper front panelof the piano-case exposes the front wall of the main exhaust chest orchamber 10. By extending the vent-duct into such front wall and locatingthe vent regulating valve therein, easy access is aiforded to the latterfor adjustment without requiring removal of the pneumatic action or anyfurther piano-case. Since the adjustment of these valves has to be madeafter the pneumatic action has been assembled and positioned within thepiano-case, it will be manifest that the described construction andlocation of the vent-regulating valves effect a dccided economy in thetime and labor required to effect their proper adjustment.

1 claim:

In a pneumatic player action of the character described, the combinationwith the action-bellows, the action-bellows valve, the diaphragmcontrolling said valve, and the tracker-range, of a main exhaust chamberhaving an unobstructed front wall and a duct formed in said front walland communicating through its lower end with one side of said diaphragmand with the tracker range, of a vent valve casing mounted in said frontwall of said exhaust chamber and communicating interiorly with saidexhaust chamber and said duct, and a needlewalve adj ustably mounted insaid valve-casing and controlling communication between the interior ofthe latter and said exhaust chamber, substantially as described.

EMORY C. HTSCOCK.

lVitnesses SAMUEL N. Penn, DAlSY C. Tnonsnx.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, D. 6.

dismantling of the

